JP5710126B2 - LED lighting device - Google Patents

Description

  The present invention relates to an illuminating device using LEDs, and more particularly to an illuminating device using LEDs in which the decrease in illuminance is small even if the illuminating device is separated from the illuminating device.

  Many illuminating devices using LEDs are known (for example, Patent Documents 1 and 2). Moreover, in order to replace the general-purpose lighting device, the appearance is similar to that of a general-purpose lighting device, and surface light emission is also known by diffusing glass light into the light transmission of the LED (for example, Non-Patent Document 1). ~ 2).

  These lighting device substitutes using LEDs have features such as having no heat, less power consumption, and longer life compared to general-purpose lighting devices. There was a problem that the illuminance was not sufficient due to the aggregate. If more LEDs are juxtaposed in order to ensure sufficient illuminance and surface illumination is used, the lighting device as a whole becomes expensive and may cause problems in terms of cost.

  In addition, as a larger problem, when more LEDs are juxtaposed, there is a problem that heat generation of the LEDs becomes a problem, and unless heat dissipation is taken into consideration, thermal destruction and illuminance rapidly decrease.

  Therefore, although the lighting device using LED has many features, it cannot be used as a complete replacement for a general-purpose lighting device due to the above-mentioned major problems, and therefore, as a general lighting device, It could not be used without any trouble.

  The demands for environmental characteristics such as energy saving and long life have been increasing in recent years. However, since the illuminance at a place away from the lighting device and at a position where the angle is shifted is insufficient, the lighting device using the LED is not general-purpose, and there is room for further improvement. there were.

JP 2009-111346 A JP 2009-286995 A RoHS product catalog (PoleLED Series)

  The present invention has been made in view of the above-described background art, and the problem is that the illuminance rapidly increases even if the LED is separated from the LED while taking advantage of the features of the LED such as suppressing heat generation, low power consumption, and long life. An object of the present invention is to provide a “lighting device in which a plurality of LED structures are juxtaposed” so that the illuminance does not drop sharply even if it is angularly deviated from the LED irradiation direction.

  As a result of intensive studies to solve the above problems, the inventor has provided a light transmissive body having a light diffusion effect in front of each LED. In addition, it was found that the illuminance does not decrease even in an oblique direction. And it confirmed that it could substitute for a general purpose illuminating device by juxtaposing a plurality of LED structures provided with such a light transmission body, and came to complete this invention.

  That is, the present invention is a lighting device having a plurality of LED structures juxtaposed and a light transmitting body in which a zinc sulfide (ZnS-Ag) compound surrounding the plurality of LED structures is diffusely arranged. The structure is provided with an “illuminating device” in which a “light transmissive body having a light diffusion effect” is provided in front of each LED.

  The present invention also provides a light transmissive LED structure in which the zinc sulfide (ZnS-Ag) compound is diffusely arranged, wherein the light transmissive body in which the zinc sulfide (ZnS-Ag) compound is diffused is a substrate buffer layer of the LED structure. The above-described illumination device is provided that has a “light refracting body having a light diffusion effect” that surrounds the upper and lower surfaces of the connecting bonding wires.

  In addition, the present invention provides the above-described illumination device that is capable of emitting light to the extent that the light illumination device is extremely thin and the contours of the individual LEDs disposed therein cannot be visually identified.

  Further, the present invention extends from the center of the illuminating device at a right angle from the illuminating device through the center of the illuminating device at an illuminance on a plane existing at a distance of 1 m from the center of the illuminating device. The illuminance at the point where the angle formed by the straight line and the plane is 10 ° is the point where the angle formed by the straight line passing through the center of the illuminating device and the plane is 90 ° (the point lowered from the center of the illuminating device perpendicular to the plane) The illuminating device is provided with the illuminance of 1/3 or more.

  According to the present invention, the heat generation is small and efficient, and the power consumption is small, so that natural resources necessary for power generation can be reduced, CO2 emissions can be reduced, the environment is friendly, and the life of the LED is long. On the other hand, it was a drawback of LEDs for lighting devices. The point of light emission is that the illuminance suddenly drops when the distance from the LED increases, and the illuminance drops suddenly when it is angularly shifted from the irradiation direction of the LED. It is possible to provide an LED surface emitting illumination device that solves the problem.

  Further, by arranging a plurality of LED structures surrounded by a light transmitting body in which a zinc sulfide (ZnS-Ag) compound is diffusely arranged, a lighting device having almost no difference in optical performance from a general-purpose lighting device can be provided. . That is, the illuminance does not decrease as much as a general-purpose lighting device even if the distance from the LED structure or the lighting device is large, and the same degree as a general-purpose lighting device even if it is angularly deviated from the irradiation direction of the LED structure or lighting device. The illuminance does not decrease. Therefore, it is possible to provide a thin illuminating device that has the same luminance as a general-purpose illuminating device in terms of use and can be used as a substitute for the illuminating device.

  Hereinafter, the present invention will be described, but the present invention is not limited to the following specific embodiments, and can be arbitrarily modified within the scope of the technical idea.

  In the lighting device of the present invention, a plurality of LED structures are juxtaposed, and each LED structure has a “light transmitting body having a light diffusion effect” (hereinafter referred to as “light transmitting body” in parentheses) in front of the LED. "Is abbreviated as").

  FIG. 1 shows a typical example of the cross-sectional shape of the LED structure 1. The LED structure 1 is provided with a light transmitting body 11 that surrounds from the irradiation direction of the p-electrode 1 in FIG. 1 (hereinafter sometimes abbreviated as “front”) to 8 substrates. The light transmitting body 11 is provided in order to obtain the above-described effects of the present invention, such as “the illuminance does not decrease even when the LED is separated from the LED” and “the illuminance does not decrease even if the angle is shifted from the irradiation direction of the LED”. The light transmissive body 11 was manufactured by the following method.

  The light transmissive body 11 is mixed with zinc sulfide (ZnS-Ag) doped with an appropriate halide such as BaCl, MgCl, or NaCl as a flux and silver sulfide Ag2S as an activator to form a mixture.

  The mixture is heated at 1250 degrees Celsius for 2 hours, and the fired product taken out from the heating furnace is washed with water, dried, classified and pulverized to make the particles substantially constant. At this stage, it is still inactive as a light transmissive body.

  After drying and classifying and pulverizing the material, the particles are roughly constant and heated together with zinc sulfide (ZnS-Ag) in a heating furnace at 730 degrees Celsius for about 8 hours and 30 minutes. The particles are washed with dilute acetic acid, washed with deionized water, activated and activated, and mixed with thermosetting silicone resin or UV curable resin as a transparent binder and put into practical use as a light transmissive body. Is done. The mixing ratio is about 7% to 15%, and becomes a light transmitting body as a mixture of activated particles and a binder.

  As shown in FIG. 2, the light transmissive body 11 constituting the LED illumination device is arranged so as to include a plurality of LEDs 13, and an LED wavelength conversion agent is provided in front of the LEDs 13.

  The LED 13 can efficiently correspond to either a UV-LED or a blue LED by selecting an activator when the light transmitting body 11 is initially fired, and a plurality of types of LEDs can also be used.

  In the LED structure, the positional relationship between the LED 13 and the light transmitting body 11 is not particularly limited, but the interval between the plurality of LEDs 13 and the LED 13 is at least 5 times the width of the cross section of the light irradiation surface of the LED 13. The point light source can be surface-emitted by the light diffusing effect by the light transmissive body 11 between the point where the LED 13 emits light and the point where the LED 13 emits light. The effect of the present invention is obtained such that “the illumination does not fall” and “the illuminance does not fall even if it is angularly shifted from the irradiation direction of the LED”.

  The light emission intensity of the LED 13 is in the vicinity of 4 and is more effective than the case where the light transmission body 11 and the plurality of LEDs 13 are changed from FIG. 2 to FIG. 4. The maximum value of the light emission intensity is 4, so a groove is formed between the LEDs. In the case of 16 in which the depth of the groove to be formed is not less than 3 times the thickness of the p-electrode surface from the substrate surface 9 of the LED, an effect can be obtained more than when the LED 13 is arranged at 14.

The shape of the lighting device of the present invention is not particularly limited, and may be any of a flat shape, a flat shape (very low height), a prism shape, and the like.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples unless it exceeds the gist.

Example 1
Since it has the same luminance as that of a general-purpose lighting device 40 type fluorescent lamp, 31 LEDs 13 were uniformly arranged on 14 aluminum substrates in the arrangement as shown in FIG. As the LED 13, a 1 mm square 350 mA chip blue LED was used at a current of 217 mA. That is, 1 mm square LEDs 13 are mounted in series at 5 mm intervals, surrounded by a light transmissive body 11 having a light diffusion effect, and bonded to a commercial power source via a constant current circuit and a rectifier diode. Wiring was done electrically. The power consumption was about ½ of the illumination device of the same shape. Moreover, the lifetime should be 10 times or more.

The diffusing agent as the light transmitting body 11 having a light diffusing effect is prepared as follows as a first heating material (ZnS: Mn, Ag), an appropriate amount of zinc sulfide containing chloride (ZnS-Ag), main Activators (by weight with ZnS) 0.1% manganese sulfate (MnSO ₄ ), 0.015% hafnium chloride HfCl ₄ , 0.5% zinc oxide (ZnO), 3% Barium chloride (BaCl ₂ ), 3% magnesium chloride (MgCl ₂ ), 0.012% iridium chloride (IrCl), 0.02% silver sulfate (Ag ₂ SO ₄ ) and 0.37% gallium oxide Ga Mixed with ₂ O ₃ , 28% sulfur and 2% sodium chloride.
The mixed material is heated at 1250 ° C. for 2 hours in a high temperature reactor.

The second stage calcination material comprises a first heat-reacted calcination material, 1% zinc sulfate ZnSO ₄ .7H ₂ O, 0.5% barium chloride (BaCl ₂ ), and 1.5% sodium chloride. Add 2% magnesium chloride (MgCl ₂ ), 3% manganese sulfate (MnSO ₄ ), 0.5% gallium Ga ₂ O ₃ , and 2.5% sulfur and load into an alumina crucible. Then, it is covered with an alumina lid and heated in a nitrogen stream at 730 ° C. for 8 hours 30 minutes to obtain cubic crystals.
This step converts the remaining hexagonal crystal ZnS to cubic crystal ZnS, which is mostly active light diffusing material. After heating, the covered crucible was removed from the furnace and cooled to room temperature, and the materials were mixed together and washed with deionized (DI) water. After 2 or 3 DI water was washed, the material was washed with acetic acid to remove unreacted ZnO and some unincorporated copper oxide. The acid washed material is washed again at least twice with DI water and then again with KCN to remove most of the residue from the light diffusing material. After washing, the light diffusing particles change from a dark gray solid color that the light diffusing particles had to a light solid color before the KCN washing.

  In this way, the light diffusing particles are classified and pulverized, and after being dried and classified and pulverized, the particles are made substantially constant, and mixed with a thermosetting silicone resin as a transparent binder to be put into practical use as a light transmitting body. Provided. The mixing ratio is about 8% to 10%, and becomes a light transmitting body as a mixture of activated light diffusing particles and a binder.

In FIG. 5, the illuminance on 17 existing at a distance of 1 m in the direction of light irradiation was measured from the center 21 of the lighting device obtained in Example 1. The illuminance was measured at a point where the straight line 17 extending perpendicularly from the lighting device had a plane angle of 90 °.
Moreover, it measured to 10 degree | times in the direction of 18 in 10 degree increments from 17-20 of the illuminating device.
The luminance was measured using a Topcon luminance meter.

Comparative Example 1
In Example 1, an illuminating device was obtained in the same manner as in Example 1 except that the light transmitting body 11 was changed to 15. That is, an illuminating device was obtained in the same manner as in Example 1 except that a transparent binder was used without using a light transmissive material having a light diffusion effect, and the illuminance was measured in the same manner. The results are shown in Table 3.

Table 1 shows the illuminance at each point. The unit in all tables is “cd / m 2”. Table 1 shows which angle the luminance is in FIG. The conditions in Table 1 are as follows: Condition A does not use the light transmitting body of FIG. 3, Condition B uses a light transmitting body having a light diffusing effect, and the groove of the substrate 16 between the LEDs of FIG. Condition C is a planar state without a groove in the substrate 16 between the LEDs in FIG.

Table 2 is a graph of Table 1. The vertical axis represents luminance (cd / m2), the horizontal axis represents 1 m from the light emitting surface 21 in FIG. 5, the surface is 90 degrees vertical, and the space 1 m parallel to the light emitting surface. 4 is a line graph up to 0. Condition B in FIG. 4 is superior in both viewing angle and luminance as compared to condition A using a light transmissive material having no light diffusion effect. The fact that the luminance is inferior compared with the state in which the groove of the substrate 16 is provided is considered to be due to the effect of providing the groove of the substrate 16 between the LEDs on the np junction surface.

  The illumination device using the LED of the present invention retains the features of the LED such as low heat generation, low power consumption, long life, etc., and the illumination intensity does not decrease even if it is away from the LED. Since the disadvantage of the illumination device using LEDs that the illuminance does not decrease even if the angle is shifted, it is not only a substitute for a general-purpose illumination device, but also a surface emitting device with surface emission. The direction can be as thin as 3 mm to 5 mm, and is widely used in all fields where illumination is used.

It is an example of sectional drawing of common LED used for the illuminating device of this invention. It is a schematic diagram shown about an example of the positional relationship of "light-transmitting body with a light-diffusion effect" of this invention, and LED. It is a schematic diagram shown about an example of the positional relationship of a "general light transmissive body" and LED. It is a schematic diagram shown about a more effective example of the positional relationship of "the light transmissive body with a light-diffusion effect" of this invention, and LED. It is a figure which shows the place which measures the angle and brightness | luminance measurement position which measure the irradiation surface of FIG.2, FIG.3, FIG.4.

1 p-electrode 2 p-layer 3 p-layer 4 pn junction layer 5 n-layer 6 n-layer 7 n-electrode 8 buffer layer 9 sapphire substrate, etc. 10 wavelength conversion layer (fluorescent layer such as yttrium)
11 Light Transmitter with Light Diffusing Effect 12 Bonding Wire (interelectrode connection)
13 LED
DESCRIPTION OF SYMBOLS 14 LED structure mounting board 15 General light transmissive body 16 Substantive focal length of photorefractive body 17 Direction of 90 degrees from light emitting surface 18 Angle of 40 degrees to light emitting surface 19 Point 1 m from light emitting surface 20 Flat illumination device (Lighting plate) Light emitting surface 21 Measurement points

Claims (2)

Method for generating a light transmitting body used for a surface emitting device having a light transmitting body having a light transmitting body in which a zinc sulfide compound (ZnS-Ag) is diffused and arranged to surround a plurality of LED structures juxtaposed on a predetermined substrate Because
Zinc sulfide containing chloride, 0.1% manganese sulfate as the main activator, 0.015% hafnium chloride, 0.5% zinc oxide , 3% barium chloride, 3% Of magnesium chloride, 0.012% iridium chloride, 0.02% silver sulfate, 0.37% gallium oxide, 28% sulfur, and 2% sodium chloride, After heating the mixture at 1250 ° C. for 2 hours, the residual flux is removed from the fired product by washing with water, dried, classified and ground to make the particles constant,
The constant particles include 1% zinc sulfide, 0.5% barium chloride, 1.5% sodium chloride, 2% magnesium chloride, 3% manganese sulfate, 0.5% Gallium and 2.5% sulfur were added, heated in a nitrogen stream at 730 ° C. for 8 hours and 30 minutes, classified and ground again, washed with deionized water, washed with acetic acid, and degassed again. After washing with ionic water, further washing with KCN produces activated particles,
The activated particles and thermosetting silicon are mixed so that the mixing ratio is 8% to 10%.
Light transmitting body generation method. An illumination device that performs surface light emission having a plurality of LED structures juxtaposed on a predetermined substrate and a light transmitting body in which a zinc sulfide compound (ZnS-Ag) surrounding the plurality of LED structures is diffused. ,
The light transmissive body includes zinc sulfide containing chloride as a flux, 0.1% manganese sulfate as a main activator, 0.015% hafnium chloride, 0.5% zinc oxide , 3% barium chloride, 3% magnesium chloride, 0.012% iridium chloride, 0.02% silver sulfate, 0.37% gallium oxide, 28% sulfur, 2% After mixing with sodium chloride and heating at 1250 ° C. for 2 hours, the residual flux is removed from the fired product by washing with water, dried and then classified and pulverized to make the particles constant. 1% zinc sulfide, 0.5% barium chloride, 1.5% sodium chloride, 2% magnesium chloride, 3% manganese sulfate, 0.5% gallium, 2.5 % Of sulfur and 730 in a nitrogen stream Activated particles produced by heating for 8 hours 30 minutes, classification and grinding again, washing with deionized water, washing with acetic acid, washing again with deionized water, and further washing with KCN And a thermosetting silicone resin, so that the mixing ratio is 8% to 10%.
Lighting device.